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OCS Report 

 MMS 2004-075

Investigation of Loss of Well Control

East Cameron Block 23

OCS-G 02853

February 17, 2004

Gulf of Mexico

Off the Louisiana Coast

 

U.S. Department of the Interior

Minerals Management Service

Gulf of Mexico OCS Regional Office
 OCS Report

MMS 2004-075

Investigation of Loss of Well Control

East Cameron Block 23

OCS-G 02853

February 17, 2004

Gulf of Mexico

Off the Louisiana Coast

Frank Pausina – Chairman

Glenn Woltman

Scott Mouton

Michael Hebert

U.S. Department of the Interior

Minerals Management Service New Orleans

Gulf of Mexico Regional Office November 2004
ii

Contents______________________________________________________

Investigation and report

Authority, 1

Procedures, 1, 

Introduction

Background, 3

Brief Description of Incident, 3

Findings

Brief Well History and Preliminary Activities, 5

Loss of Well Control and Remedial Actions, 6

Pre-Coiled Tubing Work and Inspection, 7

Well Configuration, 7

Third Party Assessment, 8

Equipment Maintenance Issues, 9

Company Management Issues, 9

Federal Regulations, 10

Conclusions

The Accident, 11

Cause of Loss of Well Control, 11

Contributing Causes, 11

Recommendations, 13

Appendix

Attachment 1 - Location of Lease OCS-G 02853, East Cameron Block 23

Attachment 2 – Photograph of Well CA-1

Attachment 3 – Photograph of Well CA-1 Tree

Attachment 4 – Photograph of Wellhead Below Workover BOP

Attachment 5 – Photograph of Injection Port

Attachment 6 – Photograph of Corroded Injection Port and Fitting
iii

Attachment 7 – Photograph of Wellhead

Attachment 8 – Photograph of Tubing Head

Attachment 9 – Wellhead Diagram
1

Investigation and Report 

Authority

A loss-of-well-control event (LWC) occurred on Dunhill Resources, Inc.’s Platform Well 

No. CA-1, East Cameron Block 23, Lease OCS- G 2853, in the Gulf of Mexico, offshore the 

State of Louisiana, on February 17, 2004, at approximately 0200 hours. Pursuant to Section 208, 

Subsection 22 (d), (e), and (f), of the Outer Continental Shelf (OCS) Lands Act, as amended in 

1978, and Department of the Interior Regulations 30 CFR 250, Minerals Management Service 

(MMS) is required to investigate and prepare a public report of this accident. By memoranda

dated March 1, 2004, and July 19, 2004, the following personnel were named to the investigative 

panel:

Frank Pausina, Chairman – Office of Safety Management, GOM OCS Region

Glenn Woltman – Office of Safety Management, GOM OCS Region

Scott Mouton – Lake Charles District, Field Operations, GOM OCS Region 

Michael Hebert – Lafayette District, Field Operations, GOM OCS Region

 

Procedures

On the morning of February 17, 2004, an inspector from the Department of the Interior, 

Minerals Management Service (MMS) district office in Lake Charles, Louisiana, visited the 

site of the incident to assess the situation, take photos, and statements. 

On February 26, 2004, the investigative panel received a written statement on the sequence of 

events from Orca Management, LLC (Orca). 

On March 5, 2004, panel members met with personnel from Orca. 
2

On March 10, 2004, panel members received the written response to the Incident of NonCompliance Form MMS-1832 issued by the MMS to Orca in February 2004. 

On March 17, 2004, the panel received copies of the wellhead manufacturer’s comments on 

the “cut-out” of the injection port on the wellhead.

In July 2004, panel members held a telecom to review all information received, the status of 

the investigation, and further informational requests. Additional interviews were deemed 

necessary. 

On July 21, 2004, members of the Investigative Panel traveled to the office of Weatherford

International Ltd.’s (Weatherford) legal representation to interview various personnel 

associated with the repair of the wellhead. 

On July 23 and August 5, 2004, members of the panel held interviews with representatives of 

Orca.

 In addition to the interviews, other information was gathered at various times from a variety 

 of sources. This information included the following reports and statements: 

• Daily Workover Reports, February 15, 2004 – February 21, 2004;

• Petroleum Professionals International’s Report on wellhead, Well No. CA-1;

• Operator’s EVACCR Incident/Accident Form, February 17, 2004;

• Form MMS-1832, Notification of Non-Compliance, February 20, 2004;

• Pictures of wellhead.

 The panel members met and discussed the evidence numerous times throughout the 

 investigation and, after having considered all of the information available, produced this 

 report. 
3

Introduction

Background

Lease OCS-G 2853 covers approximately 4,772 acres and is located in East Cameron Block 23, 

Gulf of Mexico, off the Louisiana Coast. For lease location, see Attachment 1. The lease was 

issued effective December 1, 1974. Dunhill Resources, Inc. became the Designated Operator of 

the lease on December 20, 2001.

During December 2001, Dunhill Resources Inc. acquired select properties from Linder, for which 

the sales and purchase were funded by Aquila Energy Capital. During December 2002, Aquila 

Energy Capital sold the portfolio of loans to Concert Capital Resources, LP (CCR). In April 

2003, CCR filed for foreclosure on the assets of Dunhill Resources, Inc., and during August 2003, 

Dunhill Resources, Inc., entered Chapter 11 bankruptcy. During October 2003, CCR formed

Orca Energy, LP, and Orca Management, LLC, to own and operate the former Dunhill Resources,

Inc., assets. During January 2004, Orca Energy, LP, foreclosed on a majority of Dunhill 

Resources assets. Currently, Dunhill Resources, Inc., remains in bankruptcy. Dunhill Resources,

Inc., remains technically as designated operator of the properties, with Orca Management, LLC 

(Orca), providing all services, support, and financing. For functional purposes, Orca is the 

operator of the subject lease and will be referred to as such in this report. The Operator-ofRecord anticipates that Orca will become principal on the bonds, pending resolution in 

bankruptcy court and with Minerals Management Service approval.

Brief Description of Incident

During January 2004, contract technicians arrived on the platform to assess the wellhead 

equipment, repair the actuator, and replace a wing valve. On February 15, 2004, a lift boat 

arrived on location to begin well work. Coiled tubing equipment, operated by Contractor 

personnel, was rigged-up and run in hole. Nitrogen was injected down the tubing to wash and 

clean out the sand to the target depth of 10,391 feet. As the intended target depth was neared, the

well started to flow. Wellhead pressure rapidly rose to 2,300 psig after the choke manifold was

closed. At approximately 0200 hours on the morning of February 17, nitrogen was observed
4

leaking from around the wellhead, below the BOP stack. The rig crew started pumping seawater 

as the kill fluid, and non-essential personnel were evacuated by 1100 hours. Well Control experts

arrived by 1430 hours, and the wellhead pressure was reduced to 0 psig by the next day. There

were no injuries and no pollution associated with this LWC. The injection fitting port on the 

wellhead that is used to inject a plastic energizer for the wellhead seal assembly failed. The failed 

port, together with a missing wellhead seal assembly, allowed for the LWC. 
5

Findings 

Brief Well History and Preliminary Activities

The last completion of Well CA-1 was at 10,393 feet with an initial bottomhole pressure (BHP) 

of 4,676 psi. The last recorded BHP of Well CA-1, taken in April 1991, was 1,487 psi. For 

photographs of the well and platform, see Attachments 2 and 3.

Well CA-1 had been shut-in since February 1993 because of problems associated with water 

loading. 

In June 1993, another operator, in attempting to return the well to production, was unsuccessful in 

his attempt to pull the well’s surface-controlled subsurface safety valve (SCSSV). The well 

remained shut-in until January 2004. 

On January 13, 2004, the SCSSV was successfully retrieved by wire line. At this time, sand was 

found in the wellbore, and bailing operations commenced. Bailing operations were not successful 

below a depth of 10,158 feet and problems arose with the wing valve and the surface safety valve 

(SSV). Bailing operations ceased shortly thereafter. A Weatherford technician was called out to 

assess the situation and make appropriate repairs. The wing valve was replaced on 

January 19, 2004, and a kit installed in the SSV actuator on January 23, 2004. 

On February 15, 2004, a coiled tubing unit arrived on location and on February 16, 2004, well 

work began. Nitrogen was injected through the tubing at approximately 2000 hours with a target 

depth of 10,391 feet. As the target depth was approached, the well began to flow, and the 

wellhead pressure rapidly rose to 2,300 psi after the choke manifold was closed. Workover 

reports indicated that the well started to flow and pressure increased rapidly as the sand bridges 

were removed. At approximately 0200 hours on February 17, 2004, nitrogen was observed 

leaking from the well area below the BOP stack. For a photograph of the well area below the 

BOP and grating, see Attachment 4. (It was later discovered that the leak occurred through the 

injection port on the wellhead – to be discussed later.)
6

Loss of Well Control and Remedial Actions

The crew immediately began to pump seawater as a kill fluid down the tubing and tubing/casing 

annulus. 

Between 0200 and 0600 hours, a cellulose polymer pill was pumped down the annulus, and the 

wellhead pressure dropped to 600 psig. 

Between 0600 and 1015 hours, MMS personnel arrived at the platform. The Operator reported 

observing a small sheen on the water within 7 hours of the start of the incident. Both O’Brien’s 

Oil Pollution Services and Clean Gulf Associates were notified and a fast response unit was 

called out during the night. By daylight the next morning, the sheen had disappeared. The 

Operator did estimate approximately 5 gallons of condensate went into the water.

Between 1015 and 2400 hours, pressure increased on the annulus with sand and gas blowing from 

the injection port on the wellhead. For a photograph of the injection port area (where the fitting 

was prior to the LWC), see Attachment 5. For a photograph for another corroded injection port 

and fitting on Well CA-1, see Attachment 6. The injection port welded fitting was absent. All 

nonessential personnel were evacuated by 1100 hours. Well control specialists (Boots and Coots) 

arrived on location at 1430 hours. 

On February 18, 2004, with well control experts on location, the injector head was removed from 

the BOP’s and well abandonment operations began. Kill mud (12 ppg) was pumped down the 

annulus, and pressure fell to 0 psig. Attempts were made to set PX tubing plugs by wireline; 

however, tight hole conditions resulted in the plugs hanging up. Consequently, on 

February 20, 2004, the wireline was cut and pulled out of the hole. A cement retainer was set at 

10,284 feet and heavy cement (16 ppg) was dumped on top of the retainer to a depth of 

10,270 feet. On February 21, 2004, a tubing plug was set at 2,858 feet, the tree cap was installed, 

and the coiled tubing unit and associated equipment were removed from the platform, and the 

well was temporarily abandoned. In April 2004, the well was permanently plugged and 

abandoned.
7

Pre-Coiled Tubing Work and Inspection

Prior to commencement of well work, Orca verbally asked Weatherford to inspect the subject 

wellhead, but did not specify any inspection work on that section of equipment below the grating 

(this area would have included the wellhead and casing head) prior to the coiled tubing 

procedures. Weatherford was also not given any post-verbal written specific inspection 

instructions. Weatherford found and replaced a wing valve and installed a new kit, consisting of 

a bladder and O-rings, in the actuator. Interviews with Weatherford personnel indicated that no 

attempt was made to inspect other equipment on the well.

Well Configuration

Review of Orca’s records by the panel revealed that the current completion equipment in the well 

included an isolation packer that was set at a depth of approximately 10,334 feet. Records did not 

show any historic evidence of annular casing pressure. However, during the workover activity 

herein reported, the casing pressure had increased to 1,550 psig just prior to the closing of the 

choke manifold. Afterwards, the pressure increased to 2,300 psi and the LWC began.

The injection fitting port that failed on the wellhead is designed to contain (trap) pressure around 

the pack-off assembly. Under normal circumstances, the seal assembly would have isolated the 

section of the tubing head above the pack-off from tubing/casing annulus pressure below. Once 

pressure is relieved above the pack-off assembly (as would have happened if the seal assembly 

and packing failed), the wellbore pressure below or above would be in communication with the 

injection port. Similarly, if there were no seal assembly installed in the wellhead, well pressure 

could be exerted on the injection port.

For the type of pressure that was noted on the workover reports to be exerted on the subject port, 

there had to be a source of pressure or a migration of pressure from the well itself. To have this 

pressure, either a tubing/casing communication condition or a behind-the-pipe communication 

had to exist. 
8

Third Party Assessment 

After the incident was brought under control and the well secured, Orca commissioned 

Petroleum Professionals International (PPI), an oil field engineering consulting firm in Houston, 

Texas, to witness and report observations during the removal of the damaged wellhead. For a 

photograph of wellhead and tubing head, see Attachments 7 and 8, respectively. The PPI report 

states in part that there was no evidence of any seal assembly and packing in place in the Vetco 

Gray tubing head and that there was external corrosion of the wellhead and packing injectors. For 

a photograph of wellhead showing the corrosion, see Attachment 7. For a diagram of the 

wellhead, see Attachment 9.

The seal assembly is designed with a bi-directional Chevron packing set that is energized by 

plastic packing injected through the packing ports. If the seal assembly had been present and was 

functional, by design, the pressure could not have been present at the packing injection port. 

However, with the seal assembly absent or not functional, any pressure from the well could have 

migrated to the port from above or below the seal assembly. In this incident, casing pressure was 

noted during the well kill stage of the project. 

For the seal assembly to be missing, an opportunity had to exist whereby the wellhead had been 

removed. Therefore, historic well data were requested by the panel members and were provided 

to them by Orca. From the information supplied, the wellhead on the subject well was first 

changed out on March 20, 1980, after the re-completion of the well to the current 

completion. Four years later, on August 6, 1984, according to information supplied, the wellhead

was again changed out because of leaks.

The wellhead was sent to Houston Metallurgical Laboratory (HML) in Houston, Texas, for 

further viewing or subsequent analysis. Given the data already available, the panel feels that the 

analysis is not needed for the purposes of this investigation and thus has not requested the 

findings of that analysis. 

During March 2004, post-incident inspection work was performed by Weatherford at the request 

of Orca. Forty-seven (47) wellheads and trees were inspected, including the subject well. A 

majority of the components on the wellheads and trees were found to need replacement or 
9

repair. Parts listed for replacement or repair included grease fittings, packing injection fittings, 

pipe plugs, ring gaskets, bull plugs, studs and nuts, lock screw assemblies for tubing spool, 

bonnet for annulus valve and bonnet seal ring, as well as blasting and painting requirements on 

lower wellhead connections. For most of the 47 wells inspected, including the subject well, it 

was confirmed that most components on the wellheads and casing heads were severely corroded 

and their functionality was questionable.

Discussions were held by the panel members with ABB Vetco Gray (ABB), the manufacturer of 

the wellhead equipment. ABB indicated in a written statement to the panel members that this

type of leak is extremely rare, and that they have not witnessed this type of failure on their highpressure wellhead equipment before. ABB indicated that the failure was not due to galvanic 

corrosion since the tubing head was manufactured from low-alloy (85,000 psig) material, and the 

fitting was manufactured from carbon steel. 

Equipment Maintenance Issues 

Observations by the panel members of the PPI and ABB reports, post-incident Weatherford 

inspections, and MMS on-site assessments led panel members to request a copy of Orca’s historic 

preventative maintenance records on the subject well. No records were provided that pre-dated 

Orca’s scheduled workover date. No records were provided to the panel members during the time 

frame that this well/lease was operated by previous operators.

Company Management Issues

No written work order with inspection requirements was prepared by Orca and submitted to 

Weatherford. This resulted in Weatherford only performing an above-deck inspection of 

equipment, which basically excluded the tubing head and wellhead areas.

A Job Safety Analysis (JSA) was completed neither prior to the wellhead inspection task nor 

before nor during any subsequent well workover tasks.
10

Orca neither took a lead role, nor provided support, coverage, and oversight of the work. Written 

and specific job tasks, which would have identified and assigned individuals to performing 

services, were not shown.

An employee of Island Operating Company (Island), Orca’s contracted lease operator, stated that 

(1) he was not familiar with the Orca/Island operating agreement, (2) he was not aware of the 

condition of the subject wellhead, and 3) well work operating decisions did not include Island.

Federal Regulations

Orca is in the process of becoming designated operator of the well and lease, replacing Dunhill 

Resources, Inc. The paperwork to be submitted for approval to the Minerals Management 

Service was being processed at the time of the incident. Orca mistakenly assumed that verbal 

approval had been received from Minerals Management Service to perform work on Well CA-1. 

As a result, an incident of non-compliance was issued to Orca.
11

Conclusions

The Accident

After a review of the information obtained during the investigation, it is the conclusion of this 

panel that, at approximately 0200 hours, while coiled tubing operations were underway, a leak 

developed through a severely corroded and thus metallurgically weakened plastic injection fitting 

port in the tubing head section of the wellhead equipment. The LWC resulted in an estimated 

spill of about 5 gallons of condensate into the Gulf of Mexico. 

Cause of Loss of Well Control

This LWC event was a result of the compromised plastic injection fitting port which, when 

breached, released trapped pressure to the atmosphere. Severe corrosion and metallurgical 

fatigue from extended service within the harsh “splash zone,” coupled with the absence of 

historic maintenance, caused the plastic injection port fitting to fail. Increased pressure was 

momentarily seen on the port as a result of a missing seal assembly and packing in the Gray 

tubing head. 

Down-hole gas flow between the tubing string above the isolation packer and the 7-inch casing 

migrated “over-the-top” of the 7-inch casing stub over which the tubing head is installed. 

Physical evidence showed that the failure was exacerbated by the age of the wellhead equipment 

and the close proximity to sea level within the splash zone. The fitting was severely corroded and 

metallurgically weakened. Since the well was “dead” prior to the coiled tubing work, little to no 

pressure was transmitted during that time to the plastic injection port fittings. 

Contributing Causes 

Orca management’s failure to take a lead role in providing support, coverage, and oversight of 

work constituted a contributing cause of the accident, as exemplified by the following specific 

failures:
12

(a) To inspect and maintain wellhead components, grease and lubricate the valves, and 

perform routine repair services regularly, as necessary, to ensure structural and functional 

integrity;

(b) To communicate regularly with the on-site supervision, including contracted operators 

(Island), to review and assess equipment integrity and compliance with safety policies;

(c) To describe clearly and in writing what was specifically expected of Weatherford in its

contracted work, including inspection responsibilities;

(d) To perform a thorough Job Safety Analysis (JSA) and inspection of all components prior 

to commencing the well work to ensure all safety issues and work activities had been 

addressed, and that all personnel were aware of specific duties, possible hazards, and safety 

policies; and 

(e) To have written and specific job tasks identified and assigned to individuals who would be 

performing services.

 
13

Recommendations

The MMS should issue a Safety Alert to all lessees and operators containing the following: 

1. A brief description of the accident,

2. A brief summary of the causes, and 

3. The following recommendations:

a) Lessees and Operators should review their well maintenance policies and activities.

b) Lessees and Operators should communicate clearly and in writing what is expected of 

their field representatives.

c) JSA’s should be performed for all tasks involving hazards.

The Department of the Interior Mission

As the Nation's principal conservation agency, the Department of the Interior has responsibility

for most of our nationally owned public lands and natural resources. This includes fostering

sound use of our land and water resources; protecting our fish, wildlife, and biological diversity;

preserving the environmental and cultural values of our national parks and historical places;

and providing for the enjoyment of life through outdoor recreation. The Department assesses

our energy and mineral resources and works to ensure that their development is in the best

interests of all our people by encouraging stewardship and citizen participation in their care.

The Department also has a major responsibility for American Indian reservation communities

and for people who live in island territories under U.S. administration.

The Minerals Management Service Mission

As a bureau of the Department of the Interior, the Minerals Management Service's (MMS)

primary responsibilities are to manage the mineral resources located on the Nation's Outer

Continental Shelf (OCS), collect revenue from the Federal OCS and onshore Federal and Indian

lands, and distribute those revenues.

Moreover, in working to meet its responsibilities, the Offshore Minerals Management Program

administers the OCS competitive leasing program and oversees the safe and environmentally

sound exploration and production of our Nation's offshore natural gas, oil and other mineral

resources. The MMS Minerals Revenue Management meets its responsibilities by ensuring the

efficient, timely and accurate collection and disbursement of revenue from mineral leasing and

production due to Indian tribes and allottees, States and the U.S. Treasury.

The MMS strives to fulfill its responsibilities through the general guiding principles of: (1) being

responsive to the public's concerns and interests by maintaining a dialogue with all potentially

affected parties and (2) carrying out its programs with an emphasis on working to enhance the

quality of life for all Americans by lending MMS assistance and expertise to economic 

development and environmental protection.
Western

Central

Eastern

LAKE CHARLES

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MISSISSIPPI

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NORTH PADRE IS.

MUSTANG IS.

PORT ISABEL

EAST BREAKS GARDEN BANKS

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TARPON SPRINGS

THE ELBOW ST. PETERSBURG

VERNON CHARLOTTE

HARBOR

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RANKIN

PULLEY RIDGE

DRY

TORTUGAS

DESOTO CANYON

LLOYD

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NG16-8 NG16-7

M

M Minerals Management Service

Gulf of Mexico OCS Region

U.S. Department of the Interior

STATUTE MILES

KILOMETERS

0

0

50

100

Location of Lease OCS-G02853, East Cameron Block 23

East Cameron

Block 23

OCS-G 02853

MIAMI

MIAMI

100

200

Attachment 1
Photograph of 

Well CA-1

Attachment 2

Well CA1
Photograph of Well CA-1 Tree

Attachment 3
Photograph of Wellhead Below Workover BOP

Attachment 4

General Area

of Initially

Observed LWC

Injection

Port

Area
Photograph of Injection Port

Attachment 5

Injection

Port
Photograph of Corroded Injection Port and Fitting

Attachment 6

Injection

Port and

Fitting
Photograph of 

Wellhead

Attachment 7
Photograph of 

Tubing Head

Attachment 8